This design resulted in 72 plots in 2013 (4 grit types4
application frequencies 2 controls in 4 blocks) and 44 plots in
2014 (3 grit types2 possible application frequencies 2 controls
in 4 blocks [the experiment was originally designed for 3 application frequencies, but crop canopy cover and low ambient weed seedbank abundance eliminated the need for a third application;thus, 3plots were pooled with 2plots resulting in twice as many 2experimental units compared with the 1and control treatments]).